You should back up your hard drive. You've heard it a million times, but most people don't do it. So we're going to make it easy: CrashPlan is the best backup tool. It's what you should use to back up your data, both on-site and off-site.

Features

Online backup services all share mostly the same feature set. They normally provide an capped plans for relatively low monthly costs, or unlimited plans for a little more; they offer strong encryption for keeping your data safe when it leaves your hard drive. Here are the basics:

Automatic, set-it-and-forget-it backup. You set your backup schedule (nightly, weekly, by-the-minute) and CrashPlan takes care of the rest—you don't have to remember to back up once you've set it up.

Back up locally. You can back up to any computer on your network, or any connected external drive. Assuming your house didn't burn down, the local backup is the one you'll go to first. (Just keep in mind that the off-site backup needs to be there in the event of a more catastrophic loss, like fire or theft.

Unlimited file size.

Incremental backup means CrashPlan only backs up the bits of data that have changed in a file—which means it doesn't have to back up the entire file every time something changes. This makes a big difference when you've got limited upload bandwidth.

CrashPlan keeps your files forever. Even if you delete a file locally, if it's been backed up to CrashPlan, you can restore it at any time unless you'd prefer they don't.

You can restore a file at any time from the CrashPlan client or via their web app.

Where It Excels

CrashPlan shares most of the features above with most popular online backup services. Here's what sets CrashPlan apart:

Free on-site and off-site backup. That is, you can back up locally to any folder or hard drive connected to your computer (free on-site) or you can back up to a folder on a friend's computer (free off-site). If you really don't want to pay for backup but you want on-site and off-site redundancy (frankly, if you're backing up, off-site is a must), then CrashPlan let's you do so for free. That's pretty cool.

When you are ready to pay for your backup, CrashPlan has the most bang for your buck, featuring cheap unlimited online backup with a premium CrashPlan+ account. Unlimited online backup for a single computer is as little as $3/month. An unlimited family plan (2-10 computers) starts as low as $6/month.

Where It Falls Short

CrashPlan is packed with useful features, and it's easily the most cost-effective backup option, but it's not as simple to set up as some of its alternatives. We've walked through how to set up an automated, bulletproof file back up solution with CrashPlan to walk you through the process. It's not too difficult, but you do need to set aside a few minutes to understand how it works.

The Competition

For online storage, Backblaze is probably the most compelling alternative to CrashPlan. It's roughly $4/month per computer for unlimited storage (meaning if you're backing up more than one computer, it's going to add up a lot faster than CrashPlan's 2-10 computer family plan). Backblaze is a little more user friendly than CrashPlan, and it has a very cool Locate My Computer feature that helps you track a lost or stolen device. (Sort of like Prey, a free tool we've walked through how to set up.)

For some, file-syncing service Dropbox is all they backup they need. It could not be simpler: Put a file in your Dropbox folder, it's backed up to all your Dropbox-connected computers and to Dropbox's servers. Dropbox isn't intended to be a backup service, though, and for large backups, it's not particularly well suited to the task. Depending on your backup needs, however, it could be a good option.

Last, there's the non-off-site option that's built into your Mac: Time Machine. Time Machine is still the only backup tool that made backup sexy, and if you're not compelled to perform off-site backups, Time Machine is a great tool, and assuming you've got an external drive to back up to, it's free. Just remember: If tragedy strikes in the form of a fire, for example, or theft, then your on-site backup is useless. If you care about your data enough to back it up, you should be using an online backup service in addition to your local backups.

Got an online backup service you love? Let's hear about it in the comments.

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